ABSTRACT
Information about the external world is analyzed and subdivided into separate processing streams in each of the sensory systems. That division begins at the very first stage of sensory processing within the somatosensory system: nociceptors, thermoreceptors, proprioceptors, and cutaneous mechanoreceptors transduce different stimulus properties and channel their information into separate, parallel streams. The same principle applies to the four cutaneous mechanoreceptors that are responsible for 74tactile perception. Evidence from three decades of psychophysical and neurophysiological research shows that each mechanoreceptive system (the mechanoreceptors of a single type and the pathways that convey their information to perception) serves a distinctly different function and that, taken together, these functions account for tactile perception (reviewed in Reference 1). In this chapter, we review briefly the functions of the mechanoreceptors, but we concentrate on the peripheral and cortical neural mechanisms of functions served by the slowly adapting type 1 (SA1) afferents (i.e., form and texture perception).
